Method for scraping cellular material from tissue

ABSTRACT

A dual action biopsy needle scrapes tissue of cellular thickness from a lesion during forward and rearward reciprocations of the needle along its longitudinal axis of symmetry. A first sharp edge, formed by a beveled distal end of the needle, scrapes tissue during proximal-to-distal travel of the needle. A second sharp edge is provided by a transversely disposed slot formed in the needle near the first sharp edge. The second sharp edge scrapes tissue during distal-to-proximal travel of the needle. In a first embodiment, the second sharp edge is coincident with an exterior surface of the needle. In a second embodiment, the second sharp edge is elevated with respect to the exterior surface and in a third embodiment the second sharp edge is recessed. Additional embodiments include a second slot, a channel, and a hinge for enabling pivotal movement of the second and third sharp edges.

CROSS-REFERENCE TO RELATED DISCLOSURES

This disclosure is a divisional application claiming the benefit of thefiling date of U.S. patent application entitled: “Dual Action AspirationBiopsy Needle,” by the same inventor, filed on Sep. 23, 2002, bearingSer. No. 10/065,155, now U.S. Pat. No. 6,709,408, which is acontinuation-in-part of U.S. patent application bearing Ser. No.09/682,252, entitled “Dual Action Aspiration Biopsy Needle” by the sameinventor, filed Aug. 9, 2001, now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates, generally, to aspiration biopsy needles. Moreparticularly, it relates to an aspiration biopsy needle having anenhanced cellular material collection capability.

2. Description of the Prior Art

There are three main types of biopsy procedures. In a first type, aconventional surgical incision is made and the patient's body is openedso that a surgeon may retrieve one or more large pieces of the tumor orlesion to be tested for malignancy. This type of biopsy is veryinvasive, expensive to perform, and requires a considerable recoverytime. Inventive endeavors in the field have resulted in two improvedprocedures that substantially reduce the invasiveness of the biopsyprocedure, as well as the expense of the procedure and the length of therecovery time.

The first improved procedure involves the cutting or shearing of one ormore visible pieces of the tumor or lesion by a relatively large boreneedle, This type of biopsy is known as a core tissue biopsy and isperformed with a core tissue biopsy needle. The pieces of tissue areusually about one to three millimeters in length and are thus visible tothe unaided eye. They cannot be immediately examined under a microscopebecause they are too thick for light to pass therethrough. Accordingly,they must first be sliced into a plurality of very thin slices by atissue-slicing machine. After slicing, they are then stained with atissue fixative e.g., formalin, glutaraldehyde, etc., and placed upon amicroscope slide for diagnostic purposes. For a period of timesufficient to cause crosslinking of connective tissue proteins presentin the tissue, the fixed tissue is sliced into thin sectionsapproximately eight (8) microns thick, the tissue sections are mountedon slides and cell-selective histiological stains are applied to stainthe tissue prior to microscopic examination. This non-frozen tissuepreparation technique typically requires twenty four to forty eight(24-48) hours to complete so the pathologist's diagnosis of the breastlesion may not be available until twenty four to seventy two (24-72)hours after the biopsy specimen was removed from the breast.Accordingly, histopathological examination and diagnosis of breastlesions may be much more time-consuming than the histopathologicalexamination and diagnosis of other types of lesions.

The use of a core tissue biopsy needle thus represents a significantimprovement over the more invasive surgical removal of tumor or lesionspecimens. However, the need to slice the specimens causes a delay inproviding the diagnosis, due to processing. Additionally, the diameterof core biopsy needles are typically larger than the diameter of fineneedle aspiration (FNA) needles, thereby increasing the risk ofprocedure-related complications including bleeding, pneumothorax, andbile leakage. Moreover, the use of core biopsy needles necessitates thepurchase and maintenance of tissue slicing machines. The material mustbe removed from the needle, deposited onto the machine, machine-sliced,removed from the machine after slicing, stained, and deposited onto amicroscope slide.

One example of a core tissue biopsy needle is disclosed in U.S. Pat. No.5,320,110 to Wang. The Wang structure has utility in performing apleural tissue biopsy by cutting tissue samples of the parietal pleura.Wang teaches a two needle (tube-in-tube) system having a sharp edge tofix tissue while a second needle is advanced to shear off a piece of thetissue. The device does not rely solely on a vacuum to draw in materialas in an FNA biopsy needle and tissue is sheared off in sizeable,visible pieces, i.e., not at the cellular level.

More particularly, in the Wang device, a hook engages the pleural tissueand an outer cannula is advanced to cut off the hooked piece of pleuraltissue. This two needle system is designed to reduce the chances of apneumothorax and thus represents a significant improvement over earlierbiopsy techniques. However, the diameter of the Wang needle as describedis about 4.5 mm, which is considerably larger than an FNA biopsy needleof the novel type disclosed herein which is typically no larger than20-22 gauge. The Wang needle is not designed as a fine needle aspirationdevice but is designed to cut off pieces of lung pleura. A largediameter needle like the Wang device measuring about 4.5 mm in diameteris inappropriate for fine needle biopsy procedures due to the high riskof complications from a large tissue puncture including bleeding,pneumothorax and bile leakage.

The Wang structure includes a notch formed in a first side of the largebore needle and a hole in an opposite side thereof. The tissue to be cutextends into the notch and is sliced off when the outer needle orcannula is advanced as aforesaid. No such opposing hole can be providedin an FNA biopsy needle because such hole would allow the escape ofcellular material when it is deposited directly from the syringe barrelonto a microscope slide in which the distal tip bevel and side notchmust point in the same direction.

The distal tip of the Wang outer needle is not hollow and therefore notissue cutting occurs at said distal tip. All tissue cutting occurs atthe side of the Wang needle where the notch is positioned. Thus, theWang needle collects relatively large samples in a knifing action, andperforms no scraping action capable of collecting samples at thecellular level.

Neither Wang nor any other known two needle systems include both an opendistal end and a port for cutting tissue nor is any core biopsy systemcapable of collecting samples of cellular thickness. It should also beobserved that the Wang needle is attached to a syringe barrel andincludes a pressure flap.

Other biopsy tools that collect large specimens include spring-loadedcore biopsy guns. An example of a vacuum-assisted biopsy device is theMammotome Biopsys® breast biopsy device.

The third technique is called fine needle aspiration (FNA) biopsy and isperformed with an FNA biopsy needle. An FNA biopsy needle scrapes cellsfrom the tumor or lesion that are so small as to be invisible to theunaided eye. Advantageously, the cellular material is already very thinwhen it is collected so there is no need to slice it to a thinner sizeprior to viewing it on a microscope slide because light can already passthrough the thin cell layer. The cellular material is deposited onto amicroscope slide directly from the FNA biopsy needle, stained, andviewed so that there is less time to the final biopsy report because theslicing machine and all of the handling steps necessitated thereby areeliminated. Trauma to the patient is greatly reduced because of smallerneedle diameter and because cells are scraped instead of tissue beingcut in thick pieces. Complication risk is also minimized or eliminateddue to smaller nozzle diameters.

FNA biopsy needles collect samples by aspiration; a vacuum applied tothe proximal end of a hollow needle pulls severed cellular material fromthe lesion into the lumen of the needle. The needle is then retractedfrom the soft tissue so that the cellular material in the lumen can beremoved for analysis. If more samples of the lesion are needed, thebiopsy needle is reintroduced into the lesion.

The primary distinction between an FNA biopsy needle and a core tissuebiopsy needle is that the latter cuts or slices relatively large piecesof tissue from a lesion or tumor whereas the former scrapes cellularmaterial from a lesion or tumor. By way of analogy, a core needleaspiration biopsy needle is like a knife that cuts slices of cheese andan FNA biopsy needle is like a cheese grater that scrapes small flakesof cheese.

Sometimes, however, the FNA biopsy procedure fails to collect a sampleof sufficient size to enable definitive pathological analysis. When thathappens, the physician must repeat the procedure, causing additionaltrauma to the body part undergoing biopsy and creating an additionalrisk of an adverse event.

The primary reason that conventional FNA biopsy needles are sometimesunable to collect sufficient cellular material is that the only cuttingaction occurs at the hollow distal tip of the needle. Thus, no scrapingoccurs during the retraction stroke of the needle, i.e., scraping occuronly in the forward thrust.

Although FNA biopsy needles represent a significant improvement overmore invasive procedures for performing biopsies on suspect lesions ortumors, there remains a need for an improved FNA biopsy needle thatincreases the amount of sample that may be recovered per entrance intothe lesion with one needle insertion so that multiple insertions neednot be performed to complete a biopsy procedure.

However, in view of the prior art considered as a whole at the time thepresent invention was made, it was not obvious to those of ordinaryskill in the pertinent art how the standard FNA biopsy needle could beimproved.

SUMMARY OF INVENTION

The longstanding but heretofore unfulfilled need for a biopsy needlehaving enhanced cellular material collection capability is now met by anew, useful, and nonobvious invention. The novel aspiration biopsyneedle includes a single needle of elongate, hollow construction havinga proximal end and a beveled distal end. The beveled distal end of theneedle is open and therefore forms a first sharp edge adapted to scrapecellular material when the needle is inserted into tissue. The needle isdisplaced from a proximal position to a distal position duringinsertion. The needle has a uniform diameter along a substantial part ofits extent. A slot is formed in the needle near the beveled distal end;the slot is transversely disposed relative to a longitudinal axis of theneedle. The slot is also angled relative to a transverse axis of theneedle such that a bottom of the slot is positioned distal to an openingof the slot. The opening of the slot includes a second sharp edgeadapted to scrape tissue of cellular size when the needle is displacedfrom a distal position to a proximal position. The novel structurefurther includes conventional means for applying a vacuum to a proximalend of the needle so that cellular material removed by the first sharpedge during proximal-to-distal travel of the needle is pulled into alumen of the needle and so that cellular material removed by the secondsharp edge during distal-to-proximal travel of the needle is also pulledinto the lumen. However, the novel structure also has utility when novacuum means is employed, i.e., even if it is not affixed to a syringebarrel.

Accordingly, the cellular material is deposited from the lumen of thesingle FNA needle onto a slide for microscopic inspection in the absenceof any need to slice said cellular material and to place said cellularmaterial, following staining, into a formative to preserve the tissue.

In all embodiments, the slot has a circumferential extent of about onehalf the circumference of the needle.

In a first embodiment, the second sharp edge is coincident with theexterior surface of the needle.

In a second embodiment, the second sharp edge is raised with respect tothe exterior surface of said needle, and in a third embodiment, thesharp edge is recessed with respect to said exterior surface.

In a fourth embodiment, the slot is also angled relative to a transverseaxis of the needle such that a bottom of the slot is positioned proximalto an opening of the slot and the second sharp edge thereby created iscoincident with the exterior surface of the needle.

In fifth and sixth embodiments, the second sharp edge of the fourthembodiment is elevated and recessed, respectively, relative to theexterior surface of the needle.

In a seventh embodiment, a first slot is formed in the needle as in thefirst embodiment and a second slot is formed in the needle as in thefourth embodiment. The first and second slots are longitudinally spacedapart from one another.

In an eighth embodiment, a transversely disposed channel is formed inthe needle and provides a second and a third sharp edge that arecoincident with the exterior surface of the needle.

In ninth and tenth embodiments, the second and third sharp edges,respectively, are elevated with respect to the exterior surface of theneedle and in eleventh and twelfth embodiments, the second and thirdsharp edges, respectively, are recessed with respect to said exteriorsurface.

In additional embodiments, the second sharp edge is mounted for pivotalmovement about a transversely disposed hinge. The hinge enables thesecond sharp edge to open wider relative to its non-hinged position sothat it may scrape off larger numbers of cellular material as the needleis displaced in a distal-to-proximal direction.

In still further embodiments, the third sharp edge is mounted forpivotal movement about a transversely disposed hinge and in additionalembodiments, both the second and third sharp edges are so mounted.

A primary object of the invention is to provide a fine needle aspirationbiopsy needle that collects a greater quantity of cellular material perneedle insertion than conventional fine needle aspiration biopsyneedles.

A closely related object is to accomplish the foregoing object by makinga structural change to an existing FNA biopsy needle so that physicianswill have a sense of familiarity when employing the improved needle.

A more specific object is to provide an FNA biopsy needle capable ofcollecting cellular material as the needle is reciprocated along itslongitudinal axis at a tissue collection site.

These and other important objects, advantages, and features of theinvention will become clear as this description proceeds.

The invention accordingly comprises the features of construction,combination of elements, and arrangement of parts that will beexemplified in the description set forth hereinafter and the scope ofthe invention will be indicated in the claims.

BRIEF DESCRIPTION OF DRAWINGS

For a fuller understanding of the nature and objects of the invention,reference should be made to the following detailed description, taken inconnection with the accompanying drawings, in which:

FIG. 1 is a perspective view of a first embodiment of the novelaspiration biopsy needle;

FIG. 2 is an enlarged perspective view of the distal end of the needleof said first embodiment;

FIG. 3 is an enlarged longitudinal sectional view of the parts depictedin FIG. 2;

FIG. 4 is an enlarged perspective view of the distal end of a secondembodiment;

FIG. 5 is an enlarged longitudinal sectional view of the parts depictedin FIG. 4;

FIG. 6 is an enlarged longitudinal sectional view of a third embodiment;

FIG. 7 is an enlarged longitudinal sectional view of a fourthembodiment;

FIG. 8 is an enlarged longitudinal sectional view of a fifth embodiment;

FIG. 9 is an enlarged longitudinal sectional view of a sixth embodiment;

FIG. 10 is an enlarged longitudinal sectional view of a seventhembodiment;

FIG. 11 is an enlarged longitudinal sectional view of a eighthembodiment;

FIG. 12 is an enlarged sectional view of a ninth embodiment;

FIG. 13 is an enlarged sectional view of a tenth embodiment;

FIG. 14 is an enlarged sectional view of an eleventh embodiment;

FIG. 15 is an enlarged sectional view of a twelfth embodiment;

FIG. 16 is an enlarged sectional view of a thirteenth embodiment; and

FIG. 17 is a diagrammatic view of a fourteenth embodiment where thenovel biopsy device is used with an endoscope.

DETAILED DESCRIPTION

Referring now to FIGS. 1-3, it will there be seen that the referencenumeral 10 denotes a first illustrative embodiment of the presentinvention.

The proximal end 12 of aspiration biopsy needle 10 is mounted in a LUERLOK® adapter 13 or equivalent structure to which a vacuum is appliedfrom a remote source of negative pressure, not shown, when the leadingor distal end 14 of said needle is inserted into a suspect lesion insoft tissue. The sharp leading end 14 is beveled in a well-known way toform a first sharp edge that scrapes cellular material from the lesionas it travels therethrough in a proximal-to-distal direction.

A vacuum applied to adapter 13 pulls cellular material severed from thelesion into lumen 16 of the needle. The well-known prior art procedureends at this point, i.e., the needle having a sample of the lesion inits lumen is retracted from the soft tissue and the sample is deliveredto a lab for analysis. Additional sample-taking requires additionalinsertions of the needle into the lesion.

A first innovation of this invention includes slot 18 formed in needle10, near first sharp edge 14 thereof. Slot 18 is transversely disposedrelative to a longitudinal axis of the needle. A lower end or bottom ofthe slot is distal to the open upper end thereof. A second sharp edge 20is formed at the distal edge of the upper end of the slot. Accordingly,second sharp edge 20 scrapes cellular material from a lesion when theneedle is retracted, i.e., when the needle is displaced along itslongitudinal axis in a distal-to-proximal direction.

It should therefore be understood that a physician may reciprocateneedle 10 along its longitudinal axis, collecting cells of a suspectlesion that are scraped off by the first sharp edge 14 during theproximal-to-distal portion of each reciprocation, and collectingcellular aspirate of said lesion that are scraped by second sharp edge20 during the distal-to-proximal portion of each reciprocation.

Thus, the chances of collecting a quantity of lesion that is sufficientfor analysis is greatly enhanced by the provision of second sharp edge20.

The circumferential extent of slot 18 is approximately equal to half ofthe circumference of needle 10, but that structural feature of slot 18is not critical to this invention;

the circumferential extent of said slot could be more or less than thatdescribed and depicted.

As perhaps best depicted in FIG. 3, second sharp edge 20 is coincidentor flush with the exterior surface of needle 10 in this firstembodiment.

FIG. 4 provides a perspective view of a second embodiment of needle 10where second sharp edge 20 a is elevated with respect to the exteriorsurface of needle 10 and FIG. 5 provides a longitudinal sectional viewof said second embodiment. The protrusion of second sharp edge 20 aabove the exterior surface of the needle ensures that the cellularmaterial collected when using this second embodiment should be greaterthan the amount of cellular material collected when using the firstembodiment.

FIG. 6 provides a longitudinal sectional view of a third embodimentwhere second sharp edge 20 b is recessed with respect to said exteriorsurface. The lesion, not shown, is under compression as needle 10penetrates it. Accordingly, an amount of tissue will enter into slot 18and be scraped off during distal-to-proximal travel of needle 10, eventhough sharp edge 20 b is recessed with respect to the exterior surfaceof the needle.

FIG. 7 depicts a fourth embodiment where a slot 18 a is formedtransversely to the longitudinal axis of needle 10 as in the firstembodiment, but the axis of symmetry of slot 18 a is normal to the axisof symmetry of slot 18. In other words, the bottom of slot 18 a isproximal to the open upper end of slot 18 a. Accordingly, a third sharpedge, denoted 20 c, is formed. Third sharp edge 20 c is auxiliary tofirst sharp edge 14 in that said third sharp edge scrapes cellularmaterial from a lesion during proximal-to-distal travel of needle 10.

FIGS. 8 and 9 depict fifth and sixth embodiments, respectively, wherethird sharp edges 20 d and 20 e are elevated and recessed, respectively,with respect to the exterior surface of needle 10.

A seventh embodiment, depicted in FIG. 10, includes first slot 18 of thefirst embodiment and second slot 18 a of the fourth embodiment. Therespective axes of symmetry of said slots are normal to one another andsaid slots 18 and 18 a are longitudinally spaced apart from one anotheras depicted. In undepicted variations or permutations of thisembodiment, second sharp edge 20 is elevated or recessed relative to theexterior surface of needle 10, as is third sharp edge 20 c.

FIG. 11 depicts an eighth embodiment. This embodiment, like the seventh,provides two auxiliary sharp edges to augment beveled edge 14. However,it provides a single transversely disposed channel as distinguished fromtwo transversely disposed slots. Thus, instead of slot 18, transverselydisposed channel 21 is formed in said needle 10. Channel 21 includes apair of longitudinally spaced apart undercuts that respectively formsecond and third sharp edges 20 and 20 c. Second sharp edge 20 performsin the same way as second sharp edge 20 of the first embodiment, i.e.,it functions during distal-to-proximal travel of needle 10. Third sharpedge 20 c, however, functions in the same way as third sharp edge 20 cof the fourth embodiment, i.e., during proximal-to-distal travel. Thus,first sharp edge 14 and third sharp edge 20 c function duringproximal-to-distal travel, but the amount of cellular material scrapedfrom the lesion during such sharp action may not be the same. Thiseighth embodiment is also similar to the seventh embodiment becausesecond and third sharp edges 20, 20 c are flush with the exteriorsurface of needle 10.

FIGS. 12 and 13 depict ninth and tenth embodiments, respectively, wheresecond sharp edge 20 f and third sharp edge 20 g are elevated,respectively, with respect to the exterior surface of needle 10.

FIGS. 14 and 15 depict eleventh and twelfth embodiments, respectively,where second sharp edge 20 b and third sharp edge 20 e are recessed,respectively, with respect to the exterior surface of needle 10.

FIG. 16 provides a longitudinal sectional view where second sharp edge20 is pivotally mounted by transversely disposed hinge means 22 so thatsecond sharp edge 20 may open as indicated by arcuate directional arrow24 to the position indicated in dotted lines to scrape larger numbers ofcells from the suspect lesion during distal-to-proximal travel of thebiopsy needle.

Second sharp edge 20 is biased against outward rotation. Various biasmeans such as different types of springs could be employed but thepreferred bias means is a living hinge formed of nitenol or othersuitable material. The hinge is held in its closed, FIG. 16 positionwhen the needle is traveling in a proximal-to-distal direction, i.e., asthe needle is inserted, but opens due to frictional forces created bythe lesion as depicted in dotted lines in FIG. 16 when the needle isretracted, i.e., when the needle is displaced in a distal-to-proximaldirection.

Alternatively, a control means, not depicted, under the control of thephysician, causes second sharp edge 20 to pivot about hinge means 22 insmall incremental amounts so that the depth of the cellular aspiratetaken from the lesion is controlled with precision.

It should be understood that, in addition to first sharp edge 20 of thefirst embodiment, sharp edges 20 a, 20 b, 20 c, 20 d, 20 e, 20 f, and 20g could also be provided in pivotal form and placed under the control ofthe control means.

Moreover, the cell-collection ability of each sharp edge 20, 20 a, 20 b,20 c, 20 d, 20 e, 20 f, and 20 g may be enhanced by several differingmeans. For example, empirical studies may show that the cell-scrapingability of said sharp edges is enhanced by making said sharp edgesabrasive. A polymer or polymers of the type that cellular materialclings to could be added to the sharp edge or edges. Adhesive of thetype that cellular material clings to could also be added to said sharpedge or edges.

As drawn, the cut that forms sharp edges 20, 20 a, 20 b, and 20 f isdisposed substantially parallel to the bevel cut that forms first sharpedge 14 of needle 10. Accordingly, said sharp edges scrape tissue withthe same degree of efficiency as first sharp edge 14. The scrapingaction provided by these sharp edges is during the distal-to-proximalstroke of needle 10 whereas the scraping action provided by first sharpedge 14 is during the proximal-to-distal stroke.

The cut that forms third sharp edges 20 c, 20 d, 20 e, and 20 g issubstantially normal to the cut that forms second sharp edges 20, 20 a,20 b, and 20 f. The scraping action of said third sharp edges is duringproximal-to-distal motion of the needle and as such said third sharpedges cut cellular material at the same time that first sharp edge 14cuts cellular material.

In this way, a physician can reciprocate the needle along itslongitudinal axis and obtain multiple cellular-sized samples of tissuefor analysis.

Needle 10 is used by inserting it into a lesion in a well-known way andby reciprocating it multiple times along its longitudinal axis. Eachproximal-to-distal displacement causes first sharp edge 14 and thirdsharp edges 20 c, 20 d, 20 e, or 20 g, depending upon the embodimentused, to sever cells from the lesion and a vacuum pulls such cellularaspirate of the lesion into lumen 16. Each distal-to-proximal motion,however, causes second sharp edges 20, 20 a, 20 b, or 20 f, dependingupon the embodiment used, to scrape off parts of the lesion. Thesescraped-off parts of the lesion enter into lumen 16 through slot 18,slot 18 a, or channel 21, depending upon the embodiment in use, underthe influence of the vacuum. Thus, in a single reciprocation, novelaspiration biopsy needle 10 collects at least twice the amount of lesionmaterial as would a conventional aspiration biopsy needle. The quantityof scraped-off lesion parts collected is increased with each subsequentreciprocation. In this way, a sufficient sample may be taken with asingle needle insertion followed by multiple reciprocations.

Additional quantities of lesion material may also be collected byrotating needle 10 about its longitudinal axis of symmetry after a firstset of reciprocations has been made. Additional rotations may followadditional reciprocations, it being understood that each rotationaladjustment exposes an unscraped mass of lesion until the needle has beenthrough three hundred sixty degrees of rotation.

FIG. 17 depicts how an endoscope or laparoscope 24 is used in connectionwith fine needle aspiration biopsy device 10. The well-known attachmentsto the endoscope such as a light source, camera unit, monitor, and thelike are not depicted to avoid cluttering the drawing. Syringe 26 is ofconventional construction and is connected to an elongate, flexiblepolymer tube or a guide tube 28 of the hollow, coiled cable type. Tubewire 28 may be up to one hundred fifty centimeters (150 cm) in lengthand is inserted into the operating channel of the endoscope orlaparoscope 24 as depicted. Novel fine aspiration biopsy device 10 issecured to the distal end of the tube or guide wire 28. Although it isdifficult to push device 10 to retrieve cellular material from lesion 30as in the earlier embodiments, it can be pulled to collect such cellularmaterial because it cuts at the cellular level in both forward andrearward motions. Pulling of guide tube 28 results in rearward motion ofdevice 10.

These improvements represent revolutionary improvements in the art ofaspiration biopsy needles and this invention is therefore entitled tothe status of a pioneering invention. Accordingly, the claims thatfollow are entitled to broad interpretation, as a matter of law, toprotect the heart or essence of the invention.

It will thus be seen that the objects set forth above, and those madeapparent from the foregoing description, are efficiently attained. Sincecertain changes may be made in the above construction without departingfrom the scope of the invention, it is intended that all matterscontained in the foregoing description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

Now that the invention has been described,

1. A method for scraping cellular material from tissue, comprising thesteps of: providing a fine needle aspiration biopsy needle of elongate,hollow construction having a proximal end, a beveled distal end, andhaving a uniform diameter along an extent of said needle; said beveleddistal end being open and forming a first sharp edge adapted to scrapecellular material when said needle is inserted into tissue and displacedfrom a proximal position to a distal position during insertion; forminga slot in said needle near said beveled distal end so that said slot istransversely disposed relative to a longitudinal axis of said needle, sothat said slot is angled relative to a transverse axis of said needlesuch that a bottom of said slot is positioned distal to an opening ofsaid slot, and so that said opening of said slot is in opencommunication with an exterior surface of said needle; forming said slotso that it includes a second sharp edge adapted to scrape tissue ofcellular size when said needle is displaced from a distal position to aproximal position; communicating a vacuum to said proximal end of saidneedle so that cellular material removed by said first sharp edge duringproximal-to-distal travel of said needle is pulled into a lumen of saidneedle and so that cellular material removed by said second sharp edgeduring distal-to-proximal travel of said needle is also pulled into saidlumen; providing a syringe, an endoscope having a proximal end in fluidcommunication with said syringe, and an elongate guide tube, andpositioning said elongate guide tube within an operating channel of saidendoscope; securing said fine needle aspiration biopsy needle to adistal end of said elongate guide tube; positioning said fine needleaspiration biopsy needle in operative relation to a lesion; andretracting said elongate guide tube and hence said fine needleaspiration biopsy needle so that cellular material is scraped from saidlesion as said fine needle aspiration biopsy needle is pulled from saidlesion; depositing said cellular material onto a slide, staining saidcellular material, and subjecting said cellular material to microscopicinspection in the absence of any need to mechanically slice saidcellular material.